1. Field of the Invention
The present invention relates to a headlamp, and more particularly, a headlamp for vehicles from which a light distribution patterns for low beam and high beam can be obtained from one light source by switching a position of an adjustable shade using a solenoid and a spring.
2. Description of the Related Art
U.S. Pat. No. 5,899,559, for example, discloses a headlamp including a light source, a reflector that reflects light from the light source to obtain light distribution patterns for low beam and high beam, an adjustable shade that switches a range of light reflection from the light source to the reflector, a solenoid that switches a position of the adjustable shade, and a spring that returns the switched adjustable shade to the original position.
Upon turning on the light source, light from the light source is irradiated onto the reflector. The position of the adjustable shade is switched either to a low beam position or to a high beam position, thereby to switch the range irradiated onto the reflector. For example, when an electric current is applied to a coil of the solenoid, the solenoid generates an attraction force, and the adjustable shade is switched to the high beam position. When applying of the electric current to the solenoid is stopped, the solenoid loses the attraction force, and the adjustable shade returns to the low beam position by an elastic force of the spring.
In this headlamp, a stopper mechanism is used for reliably stopping the adjustable shade at the low beam position or at the high beam position. This stopper mechanism comprises a movable side such as the adjustable shade or a plunger of the solenoid, and a fixed side such as a stopper, which abuts against the movable side. At the time of switching the position of the adjustable shade, since the movable side abuts against the fixed side, the stopping mechanism makes an annoying noise. This noise is offensive to human ears, and gives an uncomfortable feeling to passengers in a vehicle. Particularly, in a quiet vehicle, this noise becomes quite a problem.